Sonchus asper (L.) Hill
prickly sow-thistle (spiny sowthistle)
Asteraceae (Aster family)
Introduction to Vascular Plants
prickly sow-thistle (spiny sowthistle)
Asteraceae (Aster family)
Introduction to Vascular Plants
Species Information
General:
Annual herb from a short taproot; stems erect, solitary, few-branched above, glabrous, hollow, exuding milky juice when broken, 0.1-1 m tall.
Leaves:
Basal leaves lacking; stem leaves alternate, prickly- margined, lowermost with stalks but not so clearly divided (as in S. oleraceus) into blade and stalk, more or less egg-shaped, uppermost deeply pinnately cut to egg-shaped and lobeless with rounded, clasping flanges at the base, 6-30 cm long, 1-15 cm wide.
Flowers:
Heads with strap-shaped flowers, several on sometimes glandular stalks in an open, flat-topped inflorescence, relatively small, commonly 1.5-2.5 cm wide in flower; involucres 9-14 mm tall; involucral bracts lanceolate, tapering to a slender tip at the apex, glabrous except for some spreading, gland-tipped hairs; ray flowers yellow.
Fruits:
Achenes 2.5-3 mm long, with 3 or rarely 4-5 conspicuous longitudinal ribs on each face, not wrinkled; pappus of white hairlike bristles.
Illustration
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia
Ecology
Ecological Framework for Sonchus asper
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)
| Site Information |
Value / Class |
||
|
Avg |
Min |
Max |
|
| Elevation
(metres) |
410 | 204 | 1270 |
| Slope
Gradient (%) |
14 | 0 | 70 |
|
Aspect (degrees) |
223 | 45 | 350 |
| Soil
Moisture Regime (SMR) [0 - very xeric; 4 - mesic; 8 - hydric] |
4 | 1 | 6 |
| Modal
Nutrient Regime
Class |
D | ||
| #
of field plots species was recorded in: |
84 | ||
| Modal
BEC Zone Class |
CWH | ||
|
All BEC Zones (# of stations/zone) species was recorded in |
BG(6), CWH(66), IDF(4), PP(8) | ||
|
Source:
Klinkenberg 2013
|
|||
Habitat and Range
Mesic to dry roadsides, disturbed areas and gardens in the lowland, steppe and montane zones; frequent in all but N regions of BC; introduced from Europe.Status Information
Synonyms
Synonyms and Alternate Names:
Sonchus asper subsp. asper
Sonchus asper subsp. glaucescens (Jord.) J. Ball
Sonchus nymanii Tineo & Guss.